modern eyes

When we want to get a look at something we are usually most prepared to do literally that; take a glance with our eyes. Eyes generally do not provide a permanent image for us to work with, though, and is rather limited to a small band of light - the visible spectrum of electromagnetic radiation. Likewise, the size, distance, or make-up of an object can prevent our eyes from being a useful tool. Instead, we have cameras, telescopes, and other sensor devices that we can use to translate the world around us into something our eyes (and heads) can make sense of.

Satellite mounted cameras are an important tool for looking at and studying many things that would be difficult or impossible from the ground. They let us investigate and image on a scale and in finer detail than would otherwise be possible. They are not without their own limitations. Our eyes can perceive the visible spectrum, all of it, at varying levels of sensitivity. Our instrument can sense a much wider selection of wavelengths on the EM spectrum but with a caveat; the sensors are generally restricted to specific wavelengths. By working with and around these quirks, we can create visible images representing a range of data. The information that a satellite sensor can 'see' is often reliant on a few important facets of how EM waves interact with things - reflection,  absorption and transmission.